During initialization, Vermont Views tests if CPU/terminal software handshaking (XON/XOFF) is active. If XON/XOFF is active, the XON/XOFF environment flag is set to ON by vv_init(). If XON/XOFF is inactive, the flag is set to OFF.
If software handshaking is not active, Vermont Views sends out null padding characters after escape sequences to give the terminal time to process the escape sequence. If software handshaking is active, no padding characters are sent. Sending padding characters slows down screen updating significantly; therefore, it is important to avoid sending padding characters if they are not necessary.
Because the use of padding is determined by the value of the XON/XOFF environment flag, you should not change the state of XON/OFF after vv_init() is called. If you do change the state of XON/XOFF handshaking, you must notify the Vermont Views system of the change with the set environment XON flag function, se_xonflag():
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Caution: se_xonflag() does not disable or enable XON/XOFF handshaking. This function only changes the value of the global variable that tells the Vermont Views system that XON/XOFF is enabled or disabled.
